/*
  将下面异步代码使用 Promise 的方法改进
  尽量用看上去像同步代码的方式
  setTimeout(function () {
    var a = 'hello'
    setTimeout(function () {
      var b = 'lagou'
      setTimeout(function () {
        var c = 'I ♥ U'
        console.log(a + b +c)
      }, 10)
    }, 10)
  }, 10)
*/

let promise = new Promise((resovle,rejecg)=>{
    var a = 'hello'
   resovle(a)
})

let r =promise.then(value => {
    let b =  'lagou'
    return value + b
}).then(value => {
    let c =  'I ♥ U'
    return value + c
}).then(value => {
    console.log(value)

})
